under dash wire harness

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F/A Tech

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My harness burt and I have taken it out and replaced the wires but not sure how to run the harness groups. Has anybody got a picture of the harness laid out so I can see what goes with what.
Thanks
 
Although you don't indicate what kind of car you have, generally there are large clips along the bottom of the dash in which the loom will lay. To the left you will see a metal tab with a hole in it- this is where the fuse block screws to. The short end of the loom goes to the left and down the kick panel. The long end of the loom goes to the right, through the large clips, over the column and out towards the glove box. Hope this gets you started.
 
get a factory manual. if you tell us what you're working on someone will get you a link to it
 
I think what you seek is which wires are bundled together. While the Factory manual is essential for you to get all this right, I think you want someone to lay out an underdash wiring harness and send you some pictures, yes? If so we are back to what car, even what options, as they changed from year to year. Don't despair! With the number of folk on FABO and the number of us that have been hoarding parts, there's a good chance somebody can do this for you. Give us year, make, model ,Rallye or standard dash, AC or not...

You should also know that even though they are pricey, you can buy exact replica under dash wiring harnesses. M&H makes them and they are sold through Year One, but M&H sometimes has oddball stuff that is not in the Year One Catalogue.
 
Thanks everyone,
I have just purchased a 1971 Scamp with a 318. Just had tires installed , stopped at Napa for some hoses and the hand brake wire shorted and fried a few wires.

Scamp with new tires.jpg
 
I downloaded the manual but a picture of a laid out loom would be perfect. Automatic, no options. The temperature guage was not working. I measured the resistance change to the fire wall, but that is as far as I got ,now that the instrument panel is out I want to check it before putting everything together.
 
I've got one for a 1970 Dart with a standard dash all marked up (I helped M&H do their new harness for that application), but the listings in the Year One catalog shows a different part number for a 71 Valiant. Is it just the wiring at that end of the harness (like left of the column)? I can take some pics for you in the morning, but it would be great if somebody here had a standard dash 71 Plymouth harness to get just the right pics.
 
Serious suggestion: if you are going to do all this, I would suggest the you disconnect the bulkhead connectors outside the fire wall, pull the rest of that plug into the inside of the car, clean all the connectors, pack them with dielectric grease and put it all back together. Yeah it's a pain to do and nasty work you can't even see, but it might save you from a big dash fire down the road...
 

I downloaded the manual but a picture of a laid out loom would be perfect. Automatic, no options. The temperature guage was not working. I measured the resistance change to the fire wall, but that is as far as I got ,now that the instrument panel is out I want to check it before putting everything together.


Read clear through section 8 and also try a year or two earlier or later. Some service manuals have drawings of the harness routing. Even if it's burned you should be able to tie-off the various branches?

Page 424 (8-203) of the 71 Plymouth chassis manual. Look on down further there are more diagrams Cluster wiring is detailed on 8-207

424valiant.jpg
 
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Unrelated to your wiring issues, it looks like it could use leaf springs in the rear.
 
Thanks, anything would help. I was hoping that I would be able to replace just a couple of wires without removing everything but after cutting the loom I realized I would have to start from scratch. No wires were broken so I was able to replace them with the right length ok, but I taped the loom up as 1 piece over the instrument panel it didn't fit. I live in the Okanagon in B.C.
 
Thanks Everyone That's great. I will look at the springs it does have air shocks but don't hold very well.
Appreciate all the quick responses
 
Air shocks are not a great a bandaid. So when you get 'round to it...new springs and shocks will be good.

Parking brake switch ought to have been protected by a fuse. Look into what wires burned or got damaged.

I agree with pretty everything above. I've become less of a fan of dielectric grease on the connectors. Seen where oxidation occurs (turns the grease green) even with the grease. DeOxit is pretty good. The 5% can be left on the terminal as a protective. The bulkhead connectors have a foam seal in them. Replace those if they've dried out.

There's been some posts this winter about testing gages. Take a look at those. It could be something simple like a poor connection. After visual and physcal check, You can do a quick test for gage resistance and if those are OK, attach resistors to simulate sending units and connect the IVR to a 12 v source.
 
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